class Sungjuk_6_2{
	String hakbun;
	String name;
	int jumsu;
	public void set_hakbun(String hakbun){
		this.hakbun = hakbun;
	}
	public void set_name(String name){
		this.name = name;
	}
	public void set_jumsu(int jumsu){
		this.jumsu = jumsu;
	}
	void prt_data(){
		System.out.println(hakbun + " " + name + " " + jumsu);
	}
	void title(){
		System.out.println("****    상속/오버라이딩 사용       ****");
		System.out.println("****    정보통신전자공학부         ****");
		System.out.println("****     20052426 장수은         ****");
	}
}
class Sungjuk_6_2_1 extends Sungjuk_6_2{
	String grade;
	public void set_grade(String grade){
		this.grade = grade;
		
	}
	void prt_data(){
		System.out.println(hakbun + " " + name + " " + grade);
	}
	void title() {
		super.title();
	}
}
class ex_6_2 extends Sungjuk_6_2 {
	public static void main(String[] args){
		Sungjuk_6_2 test = new Sungjuk_6_2();
		test.set_hakbun("20052426");
		test.set_name("장수은");
		test.set_jumsu(84);
		Sungjuk_6_2 test2 = new Sungjuk_6_2();
		test2.set_hakbun("20071035");
		test2.set_name("김수진");
		test2.set_jumsu(95);
		Sungjuk_6_2 test3 = new Sungjuk_6_2();
		test3.set_hakbun("20082413");
		test3.set_name("장형철");
		test3.set_jumsu(75);
		Sungjuk_6_2 print = new Sungjuk_6_2();
		print.title();
		test.prt_data();
		test2.prt_data();
		test3.prt_data();
		
		Sungjuk_6_2_1 sub_test = new Sungjuk_6_2_1();
		sub_test.hakbun = test.hakbun;
		sub_test.name = test.name;
		sub_test.set_grade("A");
		Sungjuk_6_2_1 sub_test2 = new Sungjuk_6_2_1();
		sub_test2.hakbun = test2.hakbun;
		sub_test2.name = test2.name;
		sub_test2.set_grade("B");
		Sungjuk_6_2_1 sub_test3 = new Sungjuk_6_2_1();
		sub_test3.hakbun = test3.hakbun;
		sub_test3.name = test3.name;
		sub_test3.set_grade("C");
		Sungjuk_6_2_1 sub_print = new Sungjuk_6_2_1();
		sub_print.title();
		sub_test.prt_data();
		sub_test2.prt_data();
		sub_test3.prt_data();
		
		Sungjuk_6_2 mix_test = new Sungjuk_6_2_1();
		mix_test.hakbun = test.hakbun;
		mix_test.name = test.name;
		//mix_test.set_grade("A");
		Sungjuk_6_2 mix_test2 = new Sungjuk_6_2_1();
		mix_test2.hakbun = test2.hakbun;
		mix_test2.name = test2.name;
		//mix_test2.set_grade("B");
		Sungjuk_6_2 mix_test3 = new Sungjuk_6_2_1();
		mix_test3.hakbun = test3.hakbun;
		mix_test3.name = test3.name;
		//mix_test3.set_grade("C");
		Sungjuk_6_2 mix_print = new Sungjuk_6_2_1();
		mix_print.title();
		mix_test.prt_data();
		mix_test2.prt_data();
		mix_test3.prt_data();
		
	}
}
